RESUMO
BACKGROUND: To explore the value of cell morphology, immunophenotype, and gene alterations of serosal effusion in the diagnosis of lymphoma. METHODS: Serosal effusion of 69 cases of lymphoma patients were collected, including 36 cases with malignant effusion and 33 cases with nonmalignant effusion. Ordinary cytology, liquid-based cytology, cellblock, and immunocytochemical staining were performed in each case, some cases were detected by fluorescence in situ hybridization for C-MYC, BCL2, and BCL6 gene translocations. T/B cell ratio in malignant and nonmalignant serosal effusions was analyzed and compared by flow cytometry (FCM) and immunohistochemical (IHC), respectively. The prognostic value of serous effusion in diffuse large B-cell lymphoma (DLBCL) was investigated and another 20 DLBCL cases without effusion were successively selected as control. RESULTS: The number of naive lymphocytes, apoptotic bodies, and mitotic figures were more common in malignant effusions compared with nonmalignant effusions (p < .01). The top three lymphomas in malignant effusion were DLBCL (19/36, 52.8%), mantle cell lymphoma (MCL) (4/36, 11.1%, 3 blastoid variant) and high-grade B-cell lymphoma (HGBL) (4/36, 11.1%). T/B cell ratio by FCM analysis ranged from 0.00 to 0.55 (mean 0.084) in malignant effusion, and 2.58 to 984.00 (mean 249.9) in nonmalignant effusion. The difference was significant (p = .017). The T/B cell ratio by IHC analysis ranged from 0.02 to 3.00 (mean 0.200) in malignant effusion, and 2.00-100.00 (mean 34.10) in nonmalignant effusion. The difference was significant (p = .017). In the effusions involving DLBCL, most effusions were present at the time of diagnosis (57.9%); single pleural effusions were more common (36.8%). The median overall survival times of patients with malignant effusion, nonmalignant effusion and DLBCL without serous effusion were 11, 17, and 23 months respectively (p = .04). Three patients of HGBL died, and the overall survival times were 5, 8, and 9 months, respectively. CONCLUSIONS: The cytomorphological characteristics combined with immunophenotype, FCM, gene rearrangement, and other tests can diagnose and classify patients with effusion as the first symptom. The T/B cell ratio is less than 1 by FCM or IHC suggesting a malignant serosal effusion. The presence of malignant effusion in DLBCL patients is an important clue for poor prognosis.